Synthesis and some properties of the methyl ester and N,N-diethylamide of 2-azido-5-phenyl-4-thiazolecarboxylic acid

The methyl ester and N,N-diethylamide of 2-azido-5-phenyl-4-thiazolecarboxylic acid were obtained by the reaction of the corresponding 4-substituted 2-hydrazino-5-phenylthiazole with NaNO₂ in acid media. IR and UV spectroscopy were used to show that the compounds synthesized retain azide form in both the crystalline state and in solution. The reaction of azides with dicarbonyl compounds gave derivatives of 2-[5-methyl-4-acetyl-or 2-[5-methyl-4-ethoxycarbonyl-1,2,3-triazol-1-yl]-5-phenylthiazole-4-carboxylic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 710–714, May, 1993.     

Analytical Properties of Gaize- and Silicate Glue-Based Xerogels with Immobilized Chrome Azurol S

A method is proposed for the synthesis of silicic acid xerogels based on opoka aluminosilicate (gaize) and silicate glue. The physicochemical properties of xerogels were studied. The complexation of Be(II) with immobilized Chrome Azurol S was studied by electronic absorption and diffuse-reflection spectrometry and solid-phase spectrophotometry. Test procedures were developed for determining Be(II) and Al(III) in waters and soils.     

Conformational study of α-phenylthiocarbonyl compounds

Electrical and electrooptical characteristics of-phenylthioacetone,-phenylthiocyclohexanone, and-phenylthio-4-caranone have been determined and used in establishing the structure of the compounds in solution. It has been shown that the preferred conformer with respect to the bond , is the ac-conformer [(O=C-C-S)>90°], in which the gauche conformer with respect to the C-S bond is realized, with a 1,3-parallel position of the C=O and S-Ph bonds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2483–2488, November, 1991.     

Reactions of vinyl 2,3-epoxypropyl ethers with 4,5-dihydro-1H-pyrazoles

Reactions of vinyl 2,3-epoxypropyl ether and 2-(vinyloxy)ethyl 2,3-epoxypropyl ether with 4,5-dihydro-1H-pyrazoles give, respectively, 3-vinyloxy-1-(4,5-dihydro-1H-pyrazol-1-yl)propan-2-ols and 3-(2-vinyloxyethoxy)-1-(4,5-dihydro-1H-pyrazol-1-yl)propan-2-ols in 70–91% yield.     

Sulfonated and sulfoacylated poly(styrene-divinylbenzene) copolymers as packing materials for cation chromatography

Three different types of cation exchangers were produced from four basic poly(styrene-divinylbenzene) substrates with different properties. Porous PS-DVB resin beads were functionalized by sulfonation and sulfoacylation under various conditions to produce sulfonated resins with exchange capacities of 0.03-1.80 mM g(-1). The matrix with 50% of cross-linking is most suitable for updating by the proposed technique. Sulfuric and chlorosulfonic acids were used as the reagents for sulfonation. The sulfonating conditions, capacities, and the technique of the synthesis are given. The effects of parameters of the sulfonation reaction and the composition of the reactionary mixture on ion-exchange capacity of the sorbents were investigated. Selectivity and efficiency of the separation of some inorganic cations and derivatives of amines and hydrazines on the resins obtained are compared by ion chromatography with conductometric detection. As a result, the sulfoacylated resin was proved more efficient for the separation of these analytes. The resolution of the analytes strongly depends on the degree of functionalization. The best performance about 19,000 plates m(-1) was obtained using the sulfopropionylated beads with an ion-exchange capacity of 0.3 mM g(-1). The prepared sulfoacylated cation exchanger was compared with the commercially available Dionex CS-12 packing material. It was found that the separation of alkaline ions and 1,1-dimethylhydrazine (UDMH) were much better that those for the commercial material.     

Complexation and flotation of nonferrous metal ions from alkaline solutions with N-acyl-N′-(p-toluenesulfonyl)hydrazines

Surfactant properties and complexation conditions of Cu(II), Co(II), Ni(II), Zn(II), and Cd(II) ions in alkaline media with N-acyl-N′-(p-toluenesulfonyl)hydrazines, which enable their use in ion flotation processes, were studied. The efficiency of the compounds under study as collectors in aftertreatment of alkaline wastewater to remove milligram amounts of Cu(II) and other metals by ion flotation was demonstrated.     

Supramolecular Conformational Effect in Complexations of Pectin and Chitosan Polysaccharides with Some Cephalosporin and Aminoglycoside Antibiotics

The reactions of the polysaccharides pectin (Pc) and chitosan (CTS) with antibiotics of cephalosporin and aminoglycoside series were studied. The complexation between the drugs and polymers was found to occur via hydrogen bonding. Dilution of the chitosan polycation increased the probability of occurrence of the negative ions of the cephalosporin antibiotic near the chain and lowered the probability of occurrence of the positive ions of aminoglycoside antibiotics, which affected the amount of adducts. When the pectin polyanion was diluted, the opposite situation was observed.     

Electrical Conductivity of Cryptocrystalline Forms of Silica

Crystallography Reports - The electrical conductivity of natural samples of exogenous silicides has been studied. In the temperature range of 515?700 K, the conductivity increases from 1.1...     

Determination of the sorption characteristics of glauconite during extraction of a pharmaceutical from an aqueous medium

A technique for preparing enriched glauconite on the basis of a natural mineral from the Beloozyorskoe field of Saratov oblast has been developed. The results of a study of the chemical composition, surface structure, and certain physicochemical properties of the samples of the sorbent are presented. The sorption of ambroxol hydrochloride ions from aqueous solutions has been studied using natural and enriched glauconite. The sorption isotherms, are approximated by the Langmuir equation, have been obtained, and the values of the maximum sorptive capacities have been calculated. Based on the obtained data, conclusions have been drawn on using the studied natural mineral sorbents to extract the above-mentioned substance from aqueous solutions.     

Application of high-performance liquid chromatography/high-resolution mass spectrometry to the investigation of sodium 2,3-disulfanyl-1-propanesulfonate (unithiol) and products of its oxidation with hydrogen peroxide

High-performance liquid chromatography combined with high-resolution mass spectrometry has been used to study the mild oxidation of sodium 2,3-disulfanyl-1-propanesulfonate (unithiol) with hydrogen peroxide. Reference peaks have been identified for the initial substance and reaction products. A possibility of using high-performance liquid chromatography with high-resolution mass spectrometry for the Sokolovskii thiol–disulphide test has been shown.